Add 21/81 and 42/20
1st number: 21/81, 2nd number: 2 2/20
21/81 + 42/20 is 637/270.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
21/81 = 21 × 20/81 × 20 = 420/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
42/20 = 42 × 81/20 × 81 = 3402/1620 - Add the two like fractions:
420/1620 + 3402/1620 = 420 + 3402/1620 = 3822/1620 - 3822/1620 simplified gives 637/270
- So, 21/81 + 42/20 = 637/270
In mixed form: 297/270
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